I've done a lot of reading and have not yet found a good solution to the "fireplace" smell that I get in the spring and now in the summer with the high humidity.
History: My 1969, ranch home has a clay 2 flue chimney. One flue for the gas water heater or furnace in the basement (no longer used for that purpose). Second flue is for the fire place. Ash traps extend to the basement floor on both. Fireplace and part of chimney has a large build up of glazed creosote from burning green wood I believe. Most of this was removed in the fireplace area last fall. I completed removed the firebrick for the fireplace up to and including the damper.
Brick was removed to install a Harmon pellet insert. SST flex pipe run out the top of the chimney. Pink fiberglass insulation was packed around the exhaust pipe to seal the chimney. Fresh air intake was dropped down into the ash cavity that extends into the basement. Pink fiberglass around that pipe to seal air from the basement. Pellet stove worked great over the winter.
With the other flue, I would vent a cheapo TSC wood stove into it, in the basement. Just by sticking the exhaust into the hole in the flue. Worked great for years. A friend gave me a used Harmon stove to replace that unit (assuming it would perform better) and it worked well the few times I used it over the winter. It sat for a month and then when I went to fire it up, I had smoke coming out of every twist lock joint on the stove. Nothing changed, never had this before. Put a match to the hole at the flue and it would draw the flame into the flue. Cannot figure that one out....yes, all pipes are clear, flue is clear - everything. After attempting to fire it up several times, with the same issue, I gave up (still never got back to tinkering with it) - got tired of stinking up the house.
My main issue is the odor from the fireplace in the house (not basement). We had hoped by removing all of that glazed creosote brick, the smell would be gone - especially with the insulation to help prevent down drafts but we still have the issue. I believe it is all downdraft issues as when it is humid out, or if the bathroom vent fans or dryer run - the smell starts / gets worse. Open a door to draw in more air and it backs off (not ideal right now with 95+ temps outside with 90%+ humidity).
Is there a better way to form a true seal around the flue and my pellet stove flex pipe? Or a way to ensure that I am drafting out the chimney instead of down? (Aside from spending thousands on an electric, draft fan for the top of the chimney.)
We don't half @$$ stuff when we do projects, so we were quite surprised to still get an odor around the fireplace this year. I know the fiberglass insulation will let some air by, however I am not aware of a tight sealing product that can withstand the temperatures. I.e. I can't foam the chimney, etc.
Edit: I should add that I am more concerned with addressing the odor when the vent fans and dryer aren't running. I understand I am creating a negative pressure when those turn on. Other than cracking a door or window, I'm not sure of an "automatic" fix for those... Just thought I should clarify that it's the "humid day and now the house smells" issue.
Thanks for the help!
-Matt
Northern Ohio
History: My 1969, ranch home has a clay 2 flue chimney. One flue for the gas water heater or furnace in the basement (no longer used for that purpose). Second flue is for the fire place. Ash traps extend to the basement floor on both. Fireplace and part of chimney has a large build up of glazed creosote from burning green wood I believe. Most of this was removed in the fireplace area last fall. I completed removed the firebrick for the fireplace up to and including the damper.
Brick was removed to install a Harmon pellet insert. SST flex pipe run out the top of the chimney. Pink fiberglass insulation was packed around the exhaust pipe to seal the chimney. Fresh air intake was dropped down into the ash cavity that extends into the basement. Pink fiberglass around that pipe to seal air from the basement. Pellet stove worked great over the winter.
With the other flue, I would vent a cheapo TSC wood stove into it, in the basement. Just by sticking the exhaust into the hole in the flue. Worked great for years. A friend gave me a used Harmon stove to replace that unit (assuming it would perform better) and it worked well the few times I used it over the winter. It sat for a month and then when I went to fire it up, I had smoke coming out of every twist lock joint on the stove. Nothing changed, never had this before. Put a match to the hole at the flue and it would draw the flame into the flue. Cannot figure that one out....yes, all pipes are clear, flue is clear - everything. After attempting to fire it up several times, with the same issue, I gave up (still never got back to tinkering with it) - got tired of stinking up the house.
My main issue is the odor from the fireplace in the house (not basement). We had hoped by removing all of that glazed creosote brick, the smell would be gone - especially with the insulation to help prevent down drafts but we still have the issue. I believe it is all downdraft issues as when it is humid out, or if the bathroom vent fans or dryer run - the smell starts / gets worse. Open a door to draw in more air and it backs off (not ideal right now with 95+ temps outside with 90%+ humidity).
Is there a better way to form a true seal around the flue and my pellet stove flex pipe? Or a way to ensure that I am drafting out the chimney instead of down? (Aside from spending thousands on an electric, draft fan for the top of the chimney.)
We don't half @$$ stuff when we do projects, so we were quite surprised to still get an odor around the fireplace this year. I know the fiberglass insulation will let some air by, however I am not aware of a tight sealing product that can withstand the temperatures. I.e. I can't foam the chimney, etc.
Edit: I should add that I am more concerned with addressing the odor when the vent fans and dryer aren't running. I understand I am creating a negative pressure when those turn on. Other than cracking a door or window, I'm not sure of an "automatic" fix for those... Just thought I should clarify that it's the "humid day and now the house smells" issue.
Thanks for the help!
-Matt
Northern Ohio
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